Navigation system and the operating method thereof

ABSTRACT

The present invention relates in general to a navigation system, more particularly, to a navigation system and an operating method thereof, in which the navigation system shows the configuration of a complicated intersection a driver is about to enter, and displays where to turn and a progression rate of the car on the path the driver is headed to. The navigation system includes a map data memory for storing map data; an input unit including a route guiding module, in which a user inputs information and/or designates a travelling path, and the input unit provides information on a route from an entrance road of a car to an exit road from an intersection; a GPS receiver including a positioning module for detecting a present position of the car on the basis of position information provided from at least one GPS satellite; a Gyro sensor for detecting a rotation angle of the car; a controller, which uses the map data from the map data memory, route information from the input unit, information from the GPS receiver about the present position of the car, and route information from the Gyro sensor, to generate the configuration of an intersection the user is supposed to enter and an arrow indicating a driving route to the user, and to display a progression rate of the car along the route; and a display driving unit for displaying the configuration of the intersection and the arrow for route guidance, on the basis of output data from the controller, and for performing a graphic operation on the configuration, thereby a gradual progression rate of the car is indicated in the directional arrow.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates in general to a navigation system,more particularly, to a navigation system and an operating methodthereof, in which the navigation system shows the configuration of acomplicated intersection a driver is about to enter, and displays whereto turn and a progression rate of the car on the path the driver isheaded to.

[0003] 2. Discussion of the Background Art

[0004] In general, a navigation system marks on a map displayed on ascreen a present position of a moving object that is calculated on thebasis of information received from a Global Positioning System satellite(hereinafter, it is referred to as ‘GPS’).

[0005] Also, the navigation system provides a driver with any kind ofinformation the driver needs for travelling, such as, travellingdirection of the moving object, distance to a destination, presentdriving speed of the moving object, a path to the destination set by thedriver before he takes off, and an optimal path to the destination.

[0006] A navigation system or GPS is widely used in various kinds ofmoving objects including ships, aircraft, or cars, and confirms apresent position and a travelling speed of the moving object ordetermines a travelling path.

[0007] Particularly, a navigation system calculates the present positionof the moving object on the basis of radio waves (or signals) indicatinglatitude, longitude, and altitude of the moving object provided from aplurality of GPS satellites. After that, a navigation system providesmap information including the present position of the moving object tothe driver with visual or voice guidance.

[0008] Therefore, a full navigation system is a route guidance systemthat calculates a present position of a car on the basis of informationreceived from GPS and marks the present position of the car on a map ora screen.

[0009] A full navigation system also provides a driver with any kind ofinformation the driver needs for travelling, such as, travellingdirection of the moving object, distance to a destination, presentdriving speed of the moving object, a path to the destination set by thedriver before he takes off, and an optimal path to the destination.

[0010]FIG. 1 is a diagram illustrating a configuration of a related artnavigation system.

[0011] Referring to FIG. 1, a GPS receiver 102 receives position datatransmitted from a plurality of GPS satellites 100 over an antenna, anda velocity sensor/Gyro sensor 104 detects rotation angle and velocity ofthe car.

[0012] An input unit 106 is a user interface where a user inputs anykind of key signal or sets a travelling path he wants to take.

[0013] A map data memory 108 stores map data and other additionalinformation data. A CD-ROM (Compact Disk-Read Only Memory) is generallyused as the map data memory 108.

[0014] A controller 110 controls general operations of the navigationsystem. To this end, the controller 110 determines a present position ofa moving object on the basis of signals received from the GPS receiver102, and matches the determined present position of the moving object onthe map data stored in the map data memory 108.

[0015] When the user inputs a starting point and a destination throughthe input unit 106, the controller 110 searches a travelling path fromthe present position of the moving object to the destination, referringto the map data stored in the map data memory 108. Then the controller110, through a display driving unit 112, makes a display 114 show thesearched travelling path on a digital map.

[0016] A voice guidance unit 116 generates a voice through a speaker118, guiding the driver of the moving object to the travelling path.However, this voice guidance is not absolutely required for the abovedescribed navigation system.

[0017] In short, the navigation system receives GPS satellite signalsfrom a plurality of GPS satellites 100 located around the earth, andtracks down the trace of a car by detecting a travelling direction ofthe car.

[0018] Further, the navigation system provides the driver of the carwith a shortest path from the starting point to the destination.

[0019] However, drivers who are not good at map reading or who cannotread the digital map fast enough often feel inconvenient to use therelated art full navigation system because it only marks the presentposition of the car on the digital map displayed on the screen and doesnot provide any other tools to recognize the marked position.

[0020] Also, the complicated operational method thereof adds anotherinconvenience to drivers because it sometimes disturbs the drivers'concentration on driving, and it can end with car accidents.

[0021] To resolve the above problems, a Turn-By-Turn (hereinafterreferred to as ‘TBT’) navigation system is now on the market. The TBTnavigation system, unlike the full navigation system, uses an arrow toindicate in which direction the driver need to go.

[0022] Needless to say, the most fundamental yet essential function in aGUID (Graphic User Interface) of the TBT navigation system is adirection arrow.

[0023]FIG. 2 illustrates one embodiment of a traffic information servicesystem, in which a portable terminal displays guidance for anintersection, i.e. in which direction a car should turn, by using anarrow.

[0024] To get the service shown in FIG. 2, a user should access to awireless Internet by operating his portable terminal and choose ‘Trafficinformation service’. After that, he should input a destination he wantsto go to. Then, the traffic information service system displays usefultraffic information on an LCD of the portable terminal leading to thedestination by using a direction arrow.

[0025] Referring to FIG. 2, on the top end of the LCD 200 of theportable terminal is the name of an intersection (e.g., First insuranceintersection 210), and at the central portion of the LCD 200 is a leftturn directional arrow 220 for the intersection. Also, three displaysare on the right side of the directional arrow 220: a distance display230 that tells how long a distance is left to the junction of theintersection, another distance display 240 that tells how long adistance is left to the user's desired destination, and a time display250 that tells an amount of time left to get to the destination. At thebottom portion of the LCD 200 is a road name display 260, and a GPSreceiving availability display 270 which indicates whether or not GPSsignals can be received.

[0026] However, a problem with using an arrow for guiding inintersections to the destination is that a driver can be easily confusedat which road he has to turn when being in an intersection because thedirectional arrow image does not always coincide with a real road.

[0027] Moreover, in case of a complicated intersection that is usuallycomposed of several nodes and links and which cannot be indicated by onesingle node, it is hard to show the complicated intersection simply byusing a left/right turn directional arrow.

[0028] What happens when the left/right turn directional arrow isapplied to every node of a complicated intersection is that the driver(or the user) can be confused at the ever fast changing arrow.

[0029] Even though the directional arrow could be used only once at acomplicated intersection, a driver needing to enter a complicatedintersection larger and more complex than general intersections willstill be more confused, not knowing where to turn.

[0030] In the past years, navigation systems have been used to performroute guidance by using arrow images, e.g., straight, left turn, rightturn, and U-turn. This method has not been effective for real situationsbecause in many intersections the roads are connected to each other indiverse angles.

[0031] Especially, when roads connected to an intersection are verynear, the directional arrow image is rather confusing to the driver,only leaving the driver without finding into which road he should turn.

[0032]FIG. 3A through FIG. 3C illustrate usage of a directional arrow toa destination path when the intersection configuration is complicated,according to a related art TBT navigation system.

[0033]FIG. 3A illustrates a simple configuration of the realintersection seen from an entrance road of a car, in which intersectionthe entrance road is connected to several other roads.

[0034] As shown in FIG. 3A, the other roads are connected to theintersection in diverse angles. Particularly, an exit road is verydensely located to the next roads.

[0035] Therefore, what most possibly happens when the related art TBTnavigation system performs route guidance simply by using arrow images,i.e. straight, left turn, right turn, and U-turn, as shown in FIG. 3B,is that the driver misses the path he should take and goes to anadjacent road instead because there is a big difference between thearrow image direction and the direction of the actual exit road heshould go.

[0036] For instance, referring back to FIG. 3A, a total of four roadsare connected to the entrance road in different directions.

[0037] Here, the heading-up road is located on 210 degreescounterclockwise from the entrance road.

[0038] In such a case, a traditional navigation system provides thedriver with a left turn arrow image similar to the one shown in FIG. 3B.However, comparing FIG. 3B with FIG. 3A, it is evident that the leftturn arrow image is much different from the actual configuration of theroads, and thus, the driver can be confused in the intersection, notknowing where to turn.

[0039] Although the related art TBT navigation system stores a varietyof different shapes of arrow images for guidance, there still is alimitation on its guidance in the intersections due to the technicalfeatures of the information terminal for the vehicle. Hence, the TBTnavigation system could not provide an accurate arrow image for everyintersection in real life.

[0040] Moreover, storing more than one arrow image for guidance anddisplaying the arrow images to the driver consumes too much memory ofthe TBT navigation system, even though it is done as an aid of thedriver.

[0041] On the other hand, as shown in FIG. 3C, an arrow image can beflexible enough to set a free angle. However, if the roads connected tothe entrance road are densely built up and the driver gets only thearrow for guidance, it is not easy to distinguish the exit road from theother roads of the intersection.

[0042] Another problem in the related art TBT navigation system is thatit does not indicate a progression rate of the car entering to thecomplicated intersection. Thus, there is no way the driver can find outif he is actually entering the exit road as he intended.

SUMMARY OF THE INVENTION

[0043] An object of the invention is to solve at least the aboveproblems and/or disadvantages and to provide at least the advantagesdescribed hereinafter.

[0044] Accordingly, one object of the present invention is to solve theforegoing problems by providing a navigation system and an operatingmethod thereof, the navigation system quickly generating an arrow, whichreflects the configuration of a complicated intersection in order toguide a driver where to turn, displaying the arrow to the driver,providing a present position of the car to the driver and displaying apresent progression rate of the car, whereby the driver can easilysingle out the exit road he wants to go no matter how many roads areconnected to the driver's entrance road in the intersection, even whenthe intersection is made of a plurality of nodes and links and cannot beindicated by one single node.

[0045] The foregoing and other objects and advantages are realized byproviding a navigation system including a map data memory for storingmap data, an input unit including a route guide module, in which a userinputs information and/or designates a travelling path, whereby theroute guide module provides information on a route from an entrance roadof a car to an exit road from an intersection, a GPS receiver includinga positioning module for detecting a present position of the car on thebasis of position information provided from at least one GPS satellite,a Gyro sensor for detecting a rotation angle of the car, a controller,which uses the map data from the map data memory, route information fromthe input unit, information from the GPS receiver about the presentposition of the car, and route information from the Gyro sensor togenerate the configuration of an intersection that the user/driver issupposed to enter and an arrow indicating a driving route to the userand to display a progression rate of the car along the route, and adisplay driving unit for displaying the configuration of theintersection and the arrow for route guidance on the basis of outputdata from the controller and for performing a graphic operation on theconfiguration, whereby a gradual progression rate of the car isindicated in the directional arrow.

[0046] In an embodiment of the invention, the map data includes aplurality of nodes and links and configuration points, namelylatitude/longitude coordinates, composing the complicated intersection.

[0047] In another embodiment of the invention an entrance link of thecar in the intersection, the entrance link being extracted from the mapdata memory, is headed up.

[0048] In further another embodiment of the invention, as for theheading up, calculations of relative angles between a travellingdirection of the car and other roads connected to the intersection arederived from a table of trigonometric function.

[0049] In still another embodiment of the invention, as for indicatingthe progression rate of the car in the intersection, the arrow for routeguidance is gradually filled or emptied.

[0050] According to another aspect of the invention, an operating methodof a navigation system includes the steps of obtaining information abouta complicated intersection, caculating heading up and screencoordinates, displaying the complicated intersection based on the screencoordinates being converted, displaying a route that passes through thecomplicated intersection and gradually changing the colour of the routeto be correspondent to a present position of the car, thereby indicatinga present position of the car on the route.

[0051] In again another embodiment of the invention, calculating headingup and screen coordinates is performed on the basis of information inputto a controller, and the configuration of the complicated intersectionis headed up through a rotation around a connection node of an entrancelink, and absolute latitude/longitude coordinates are converted to thescreen coordinates of the car.

[0052] Therefore, the navigation system of the invention displays on theinformation screen for a vehicle the configuration of the complicatedintersection connected to the entrance road of the car by using thedirectional arrow showing the travelling path the driver should take inthe intersection, and at the same time graphically shows the progressionrate of the car based on the present position of the car in thecomplicated intersection, thereby providing a high quality service withbetter visibility to the driver.

[0053] Also, generating and displaying the directional arrow forguidance in intersections and the rough configuration of theintersection do not take much of calculation. Hence, the navigationsystem of the invention can be applied to small capacity terminals.

[0054] Additional advantages, objects, and features of the inventionwill be set forth in the part in the description which follows and willbecome apparent to those having ordinary skill in the art uponexamination of the following or may be learned from practice of theinvention. The objects and advantages of the invention may be realizedand attained as particularly pointed out in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The invention will be described in detail with reference to thefollowing drawings in which reference numbers refer to correspondingelements and wherein

[0056]FIG. 1 is a diagram illustrating a configuration of a related artnavigation system;

[0057]FIG. 2 illustrates one embodiment of a traffic informationservice, in which a portable terminal displays guidance for anintersection, i.e. an intersection at which a car should turn, by usingan arrow;

[0058]FIG. 3A through FIG. 3C illustrate usage of a directional arrow toan exit road, when an intersection has a complicated configuration,according to a related art TBT navigation system;

[0059]FIG. 4 is a block diagram illustrating components of a navigationsystem of the present invention, in which guidance for intersections anda progression rate of a car in a complicated intersection is provided;

[0060]FIG. 5 is a flow chart describing a general procedure of anavigation system of the present invention;

[0061]FIG. 6 illustrates one embodiment of a real life complicatedintersection connected to an entrance road of a car, indicating how tofigure out the configuration of the complicated intersection;

[0062]FIG. 7A through FIG. 7C illustrate a rough configuration of acomplicated intersection and a progression rate of a car in theintersection, using an arrow directing to a path the car is headed to;and

[0063]FIG. 8 is a flow chart describing an operating method of anavigation system of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0064] The following detailed description will present a navigationsystem and an operating method thereof according to a preferredembodiment of the invention in reference to the accompanying drawings.

[0065]FIG. 4 is a block diagram illustrating components of thenavigation system of the present invention, in which guidance forintersections and a progression rate of a car in a complicatedintersection is provided.

[0066] Referring to FIG. 4, the navigation system according to thepresent invention includes a map data memory 440 for storing map dataincluding a plurality of nodes and links and configuration pointsthereof that compose complicated intersections, an input unit 430, inwhich a user inputs information or designates a travelling path, theinput unit 430 providing information on a route from an entrance road ofa car to an exit road from an intersection connected to the entranceroad, a GPS receiver 420 including a positioning module 420 a thatdetects a present position of a car on the basis of position informationof the car provided from at least one GPS satellite 400, a Gyro sensor470 for detecting a rotation angle of the car, a controller 410, whichuses the map data from the map data memory 440, route information fromthe input unit 430, information from the GPS receiver 420 about apresent position of the car and route information from the Gyro sensor470 to generate the configuration of an intersection the car user/driveris supposed to enter and an arrow indicating a driving route to the userand to display a progression rate of the car along the route, and adisplay driving unit 450 for processing, on the basis of output datafrom the controller 410, a TBT graphic using a TBT graphic part and userI/F (interface) part 450 a, whereby a gradual progression rate of thecar is indicated in a directional arrow over the configuration of theintersection and displayed on a display 460.

[0067] The navigation system of the present invention performs headingup on an entering link of the car in the intersection. Here, ‘headingup’ means placing the travelling direction of the car indicates theupper part of the screen all the time.

[0068] In other words, the travelling direction becomes 0 degree, andthe other connected roads are expressed in terms of relative angles tothe travelling direction.

[0069] The reference of heading up is a node, or an intersecting point,where the entrance road is connected to the complicated intersection.Also, an arrow indicates the travelling direction starting from a pointwhere the car has not yet reached the node.

[0070] As for the heading up, the system derives calculations ofrelative angles between the travelling direction of the car and otherroads connected to the intersection, using a table of trigonometricfunction (e.g., if a reference is made to sin 30, SIN_TABLE[30] isused).

[0071] To indicate the progression rate of the car in the complicatedintersection, the controller 450 constantly receives from thepositioning module 420 a of the GPS receiver 420 information about thepresent position of the car, and controls the display driving unit 450to graphically-fill/empty the directional arrow for guiding on theentering route and in the configuration of the displayed complicatedintersection step by step.

[0072] An operation of the navigation system including the abovedescribed structure is now explained below.

[0073] An information terminal for a vehicle mounted with a TBTnavigation system includes the GPS receiver 420 including thepositioning module 420 a. The information terminal for the vehicleobtains a position information of the car by receiving wave signals fromGPS satellites, stores the position information in the map data memory440 equipped in the car, and figures out a present position of the car.

[0074] When the user/driver inputs a destination through the input unit430, the information terminal for the vehicle selects an optimum routeor a shortest route to the destination.

[0075] If the driver in order to get to the destination has to gothrough many intersections or a complicated intersection connected toother roads in a complicated way, the navigation system performs thefollowing.

[0076] At first, the system marks the body of the directional arrow forguidance on the configuration of the complicated intersection connectedto the entrance road where the car is at and on the links of a path fromthe entrance road to the exit road the driver needs to take to get tothe destination by using a corresponding colour on the body of thearrow.

[0077] The navigation system puts the head of the arrow on a startingnode of the link for exiting the complicated intersection, and shows thedriver from which direction he should enter and to which direction heshould exit.

[0078] To obtain the configuration of the complicated intersection, itis necessary to know all roads connected to the intersection withrespect to the entrance road of the car, and to calculate relativeangles between the entrance road and the intersection and between roads.In this manner, phases between roads composing the intersection can bediscovered.

[0079] Here, when the configuration of the complicated intersection isextracted from a digital map in the terminal and displayed on a terminalscreen, the navigation system performs heading up of the configurationwith respect to the entrance link (i.e. places the configuration at theupper part of the screen in consideration of visibility).

[0080] Besides the heading up, route guidance of a TBT navigation systemalways places the entrance road in the vertical direction so that theentrance road is used as a reference for other roads.

[0081] That is to say, an entrance road inclined by a certain angle fromtrue north is placed in a vertical line, and angles between the entranceroad and each of the other roads are measured to express other roads.

[0082] To figure out the configuration of the intersection by headingup, the navigation system usually performs trigonometric functionoperations using a table of trigonometric function instead of atrigonometric library.

[0083] For instance, sin 30+ can be referred to the table oftrigonometric function, which is SIN_TABLE[30], or to be more specific,a desired result can be found in a one-dimensional array of the table.

[0084] In short, the table of trigonometric function is very convenientto use because it provides a trigonometric function value right away.However, when the trigonometric function library is used, the navigationsystem needs to do floating pointer operations which require much morecalculation and take longer time.

[0085] Then the route guide 430 a provides the thusly obtainedconfiguration of the intersection to the controller 410, eventuallyproviding the driver with the path he is supposed to take.

[0086] Using the information from the route guide 430 a, the controller410 controls the display driving unit 450 to display the path the drivershould take from the complicated intersection in the shape of an arrowpointing to the path.

[0087] Also, the controller 410 figures out which part of thecomplicated intersection the car is located at, by the aid of the GPSreceiver 420 including the positioning module 420 a. Then, in order tomark the progression rate of the car, the controller 410 controls thedisplay driving unit 450 to gradually fill or empty the path in theshape of the arrow.

[0088] Another way of marking the progression rate of the car ischanging the colour of the arrow step by step as the car approaches theexit road, or filling the arrow starting from a start node of theentrance node/road.

[0089] With reference to FIG. 5, the general operating method of thenavigation system of the present invention is now discussed.

[0090] The navigation system obtains information about the complicatedintersection namely node(s) of the intersection the car is now entering,link(s), latitude/longitude coordinates, and true north, through thepositioning module and the map data memory (S501).

[0091] To calculate heading up and screen coordinates, the navigationsystem uses the information input to the controller, rotate withcentering around the connection node of the entrance link and performheading up and convert absolute latitude/longitude coordinates to screencoordinates. (S 502).

[0092] Based on the converted screen information, a complicatedintersection and a route going through the complicated intersection isgenerated and displayed on the display with an arrow (S 503, S504).

[0093] Receiving the position information of the car on the path fromthe positioning module, the navigation system gradually changes thecolour of the directional arrow representing the path the driver needsto follow, keeping pace with the travelling link (S505).

[0094]FIG. 6 illustrates one embodiment of a real life complicatedintersection connected to an entrance road of a car, indicating how tofigure out the configuration of the complicated intersection.

[0095] Based on the information stored in the map data memory 440, everynode and link and configuration points (latitude/longitude coordinates)that comprise the complicated intersection are derived.

[0096] For heading up, a relative angle of the entrance link to truenorth is also derived.

[0097] The complicated intersection can be expressed in different links,in dependence of the travelling direction of the car.

[0098] Centering around connection nodes of the entrance link, allconfiguration points are turned and headed up, as shown in FIGS. 7A, 7B,and 7C. After that, latitude/longitude coordinates of every node andlink and configuration points composing the complicated intersection areconverted to screen coordinates.

[0099] In other words, the entrance link is placed in the verticaldirection, and using the heading up reference point as the origin, thenavigation system revolves the path toward the exit road as much as arotation angle. Then, the path the driver should take from thecomplicated intersection is easily visible.

[0100] The configuration of the complicated intersection is laterdisplayed on the screen of the terminal, as shown in FIG. 7A.

[0101] Next, as shown in FIG. 7A, the links of the path provided by theroute guidance data input unit are coloured in the same colour as thebody of the arrow.

[0102] Here, the arrow mark is displayed on the configuration of thecomplicated intersection obtained by using phase data of each link withrespect to the path the car should follow in the complicatedintersection that is calculated in the route guide 430 a, on the basisof the table of trigonometric function.

[0103] At this time, the head of the arrow points to the start node ofthe exit link from the complicated intersection.

[0104] Both FIG. 7A and FIG. 7C illustrate the configuration of thecomplicated intersection and the progression rate of the car in theintersection, using the arrow directing to the path the car is headedto.

[0105] Referring to FIG. 7A, the configuration of the complicatedintersection is displayed centering on the entrance road {circle over(1)} that is headed up in the vertical direction. After finding out thepresent position of the car through the positioning module 420 a, thenavigation system marks the path the driver should take connecting theentrance road {circle over (1)} to the exit road {circle over (2)} onthe configuration of the complicated intersection.

[0106] As depicted in FIG. 7B, the body of the directional arrowindicating the path the driver should follow in the complicatedintersection connected to the entrance road {circle over (1)} of the caris being graphically filled little by little.

[0107] The changing progression rate of the car in the arrow can beindicated in diverse ways. For example, the colour of the arrow can bechanged gradually from the start point, or the colour of the arrow canbe erased gradually along the motion of the car.

[0108]FIG. 7C illustrates the completely filled directional arrowgraphic, indicating that the driver has just gone though the complicatedintersection.

[0109]FIG. 8 is a flow chart describing an operation method of thenavigation system according to the present invention.

[0110] The navigation system constructs a map database including acomplicated intersection composed of at least one intersection (S801).

[0111] Applying the general Turn-By-Turn method, in which a travellingdirection of the car is indicated by an arrow, the navigation systemshows a route the driver should take in the intersection (S802).

[0112] While the driver is driving, the navigation system figures outwhether or not a next entrance road is a complicated intersection, onthe basis of information from the map data memory and the GPS receiver(S803). If the next entrance road is a complicated intersection, thenavigation system extracts the configuration of the correspondingcomplicated intersection and displays the configuration on the screen(S804).

[0113] To display the travelling direction in the intersection, thenavigation system calculates a rotation angle with respect to true northof the entrance link, using node information stored in the map datamemory, and then performs heading up. Then, the navigation systemconverts the latitude/longitude coordinates stored in the database toscreen coordinates (S805).

[0114] To be correspondent to the present position of the, car givenfrom the positioning module of the GPS receiver, the navigation systemindicates the travelling direction the driver should go by graduallychanging the graphic colour of the arrow displayed along the travellingpath (S806).

[0115] Meanwhile, if the driver (or the user) wants, the progressionrate of the car can be displayed not only for the complicatedintersection but also for general intersections.

[0116] In step 806 for indicating the progression rate of the carcorresponding to the position of the car in the complicatedintersection, the controller to which the present position of the car isinput and the graphic I/F (interface) are responsible for graduallychanging the graphic colour of the arrow as the car moves along thepath.

[0117] In conclusion, the present invention relates in general to thenavigation system and the operating method thereof, in which thenavigation system shows the configuration of the complicatedintersection the driver is about to enter, and displays where to turnand a progression rate of the car on the path the driver is headed to.

[0118] Therefore, the navigation system of the invention displays on theinformation screen for a vehicle the configuration of the complicatedintersection connected to the entrance road of the car by using thedirectional arrow showing the travelling path the driver should take inthe intersection, and at the same time graphically shows the progressionrate of the car based on the present position of the car in thecomplicated intersection, thereby providing a high quality service withbetter visibility to the driver.

[0119] Also, generating and displaying the directional arrow forguidance in intersections and the rough configuration of theintersection do not take much of calculation. Hence, the navigationsystem of the invention can be applied to small capacity terminals.

[0120] While the invention has been shown and described with referenceto certain preferred embodiments thereof, it will be understood by thoseskilled in the art that various changes in form and details may be madetherein without departing from the spirit and scope of the invention asdefined by the appended claims.

[0121] The foregoing embodiments and advantages are merely exemplary andare not to be construed as limiting the present invention. The presentteaching can be readily applied to other types of apparatuses. Thedescription of the present invention is intended to be illustrative, andnot to limit the scope of the claims. Many alternatives, modifications,and variations will be apparent to those skilled in the art. In theclaims, means-plus-function clauses are intended to cover the structuresdescribed herein as performing the recited function and not onlystructural equivalents but also equivalent structures.

What is claimed is:
 1. A navigation system, comprising: a map datamemory for storing map data; an input unit including a route guidemodule, in which a user inputs information and/or designates atravelling path, whereby the route guide module provides information ona route from an entrance road of a car to an exit road from anintersection; a GPS receiver including a positioning module fordetecting a present position of the car on the basis of positioninformation provided from at least one GPS satellite; a Gyro sensor fordetecting a rotation angle of the car; a controller, which uses the mapdata from the map data memory, route information from the input unit,information from the GPS receiver about the present position of the car,and route information from the Gyro sensor, for generating theconfiguration of an intersection the user is supposed to enter and anarrow indicating a driving route to the user, and for displaying aprogression rate of the car along the route; and a display driving unitfor displaying the configuration of the intersection and the arrow forroute guidance on the basis of output data from the controller, and forperforming a graphic operation on the configuration, whereby a gradualprogression rate of the car is indicated in the directional arrow. 2.The navigation system according to claim 1, wherein the map dataincludes a plurality of nodes and links and configuration points, namelylatitude/longitude coordinates, composing the complicated intersection.3. The navigation system according to claim 1, wherein an entrance linkof the car in the intersection, the entrance link being extracted fromthe map data memory, is headed up.
 4. The navigation system according toclaim 3, wherein when the entrance link of the car in the intersectionis headed up, calculations of relative angles between a travellingdirection of the car and other roads connected to the intersection arederived from a table of trigonometric function.
 5. The navigation systemaccording to claim 1, wherein as for indicating the progression rate ofthe car in the intersection, the arrow for route guidance is graduallyfilled or emptied.
 6. The navigation system according to claim 1,wherein the travelling route for the car is expressed by linksconnecting nodes.
 7. The navigation system according to claim 1, whereina head of the arrow points at a start node of the exit link getting outof the complicated intersection, thereby indicating from which directionthe user comes and for which direction the user is heading.
 8. Anoperating method of a navigation system, comprising the steps of:obtaining information about a complicated intersection; calculatingheading up and screen coordinates; displaying the complicatedintersection based on the screen coordinates being converted; displayinga route that passes through the complicated intersection; and graduallychanging the colour of the route to be correspondent to a presentposition of the car, thereby indicating a present position of the car onthe route.
 9. The method according to claim 8, wherein to obtain theconfiguration of the complicated intersection based on information aboutthe complicated intersection, nodes, links, and latitude/longitudecoordinates of the intersection being ahead, and the true northdirection are obtained from a map data memory of the navigation system.10. The method according to claim 8, wherein calculating heading up andscreen coordinates is performed on the basis of information input to acontroller of the navigation system and the heading up is performed byrotation with centering around a connection node of an entrance link,and the screen coordinates is performed by converting absolutelatitude/longitude coordinates to the screen coordinates of the car. 11.An operating method of a navigation system, comprising the steps of:constructing a map database including a complicated intersectioncomposed of at least one intersection; displaying a driving route in theintersection, applying a Turn-By-Turn method; using information providedby a map data memory and GPS receiver and obtaining whether an entranceroad is part of a complicated intersection; if the entrance road is partof a complicated intersection, extracting the configuration of thecorresponding complicated intersection from the map data memory, anddisplaying the configuration; displaying a travelling direction of a carin the intersection; and gradually changing an arrow displayed on thetravelling direction of the car while keeping pace with a presentposition of the car provided from a positioning module of a GPSreceiver.
 12. The method according to claim 11, wherein to display thetravelling direction in the intersection, node information stored in amap data memory is extracted and a true north direction value of theentrance road is calculated to perform heading up and to convertlatitude/longitude coordinates stored in a database to screencoordinates.
 13. The method according to claim 11, wherein to indicate aprogression rate of the car to be correspondent to the present positionof the car in the complicated intersection, a controller controls agraphic interface of the navigation system to gradually change thecolour of an arrow on the travelling route, based on positioninformation of the car provided by a positioning module of thenavigation system.
 14. The method according to claim 11, wherein aprogression rate of the car is indicated not only for complicatedintersections but also for general intersections.